In the closing minutes of “Therefore I Am,” after Cisco (Carlos Valdes) gives the name of The Thinker to DeVoe ...

... Wally is cheerfully greeted by the members of Team Flash upon his return. When Barry asks how Blue Valley was, Wally says that “self-reflection and a battle with a starfish from outer-space gives you perspective.”

Now, the one starfish from outer-space that we know of from the pages of DC Comics is Starro the Conqueror, a massive supervillain that resembles a starfish (See Exhibit A Below) created by Gardner Fox and Mike Sekowsky in 1960 for Brave and the Bold #28. Starro was actually the baddie who led to the creation of the Justice League of America in the same comic and boasted mind-control powers.

Although defeated by original JLA team members Aquaman, Flash (Barry Allen), Wonder Woman, Green Lantern (Hal Jordan) and Martian Manhunter, Starro returned many times to wreak havoc on various other superheroes and a different version of Starro even took control of Barry and the inhabitants of Blue Valley by using spores at some point.

Since the mention was brief in last night's episode there’s no way to know exactly if this is what happened to Wally, but it's fun to imagine that it did. For now, it's likely to take this one as a fun easter egg, because bringing Starro to life wouldn't just be tough — it'd likely be a budget buster. The Flash returns next week with “Crisis on Earth-X.”